The subject matter of this application is related to control of recording devices, such as hard disk drives.
Storage devices such as a disk drive can store data on circular, concentric tracks on a disk surface. For example, a disk drive can include one or more rotatable recording disks, which can be optical or magnetic, and are axially aligned and mounted to a spindle motor for rotation. A disk drive can include one or more read-write heads configured to retrieve and record data on a magnetic layer of a rotating disk as the head flies on a cushion of air over the disk surface. When retrieving data, magnetic field variations perceived by a read-write head are converted into an analog electrical signal, the analog signal can be amplified, converted to a digital signal, and interpreted.
A disk drive can use various motors for actuating different drive components. For example, a disk drive can control a motor, e.g., spindle motor, to rotate a structure holding one or more disks. The disk drive can control a different motor, e.g., voice coil motor (VCM), to move a read-write head about a surface of a disk.